package io;

public class Demo {
    public static void main(String[] args) {
        //返回当前系统时间毫秒值。返回值表达UTC时间
        //UTC时间:1970-01-01 00:00:00到该long值所经过的毫秒
        long time = System.currentTimeMillis();
        System.out.println(time);

        time = time/1000/60/60/24/365;
        System.out.println(time);

        time = Long.MAX_VALUE;//long最大值
        time = time/1000/60/60/24/365;//最多经过多少年
        System.out.println("公元:"+(1970+time));
    }
}
